Asia Defense | Security | Oceania

Australia-Japan Ink Deal for Mogami-class Frigates

Canberra and Tokyo continue to build closer links with each other, with a shared understanding of the strategic environment, and a high degree of trust

Last week Australia and Japan signed a new agreement for the Australian Navy to acquire Japanese-designed Mogami-class frigates. The agreement follows up on the Albanese government’s decision last August to award the project to Japan’s Mitsubishi Heavy Industries (MHI). Countries like Australia are seeking to diversify their military hardware away from the United States, as the deal demonstrates. Canberra and Tokyo continue to build closer links with each other, with a shared understanding of the strategic environment, and a high degree of trust. 

The deal addresses a significant Australian capability gap. Australia’s ageing Anzac-class frigates are increasingly vulnerable in an era defined by long-range precision strike, drones, and undersea competition. The Mogami-class vessels are designed with stealth characteristics, advanced sensors, and the capability to serve a range of different missions. This is a significant upgrade, enhancing anti-submarine warfare, air defense, and greater long-range strike capabilities. 

The planned fleet will consist of 11 vessels, with the first three constructed in Japan and the remainder in Western Australia. This is consistent with Australia’s new approach to defense hardware, which seeks to build local construction capabilities and seek significant technological transfer. For Tokyo, this is a big step, as it usually is incredibly cautious about sharing technology. 

Alongside the practical implications, there is a symbolic element. This is the largest defense hardware agreement since Japan lifted its arms export ban in 2014, signaling a high degree of trust between Tokyo and Canberra. This marks a further step for Japan in normalizing its role as a military power. 

The Australia-Japan relationship has undergone a significant transformation over the past two decades. Once defined primarily by trade – particularly energy exports from Australia to Japan – it has evolved into an increasingly intimate defense relationship. 

This trajectory accelerated after Japan’s 2014 relaxation of its arms export restrictions, which allowed Tokyo to begin participating in international defense markets. The Mogami deal is, in this sense, a culmination of that shift: Japan is no longer just a security consumer under the U.S. alliance system, but an increasingly active provider of security capabilities.

Although Australia continues to bet on an unreliable United States as the central pillar of its defense posture, the new National Defense Strategy does recognize the need to deepen partnerships with other powers in the Indo-Pacific, with Japan being the prime “key partner.” There is an understanding that middle powers must demonstrate the capability to contribute meaningfully to regional security. It is likely that Australia’s Defense Department realizes that Washington is now unreliable; it’s just unwilling to say so openly.

The frigate deal embeds middle power cooperation into industrial practice. The decision to build eight of the vessels in Western Australia is not merely about domestic jobs and enhancing Australia’s defense industry; it represents a deeper integration of defense industrial bases. It is about building the habits of cooperation within the full spectrum defense activity from the shop floor up to coordinated strategy and exercises.  

This has long-term implications. Defense industrial cooperation tends to create path dependencies: shared supply chains, common maintenance requirements, and aligned upgrade cycles. Over time, these generate an integration that extends beyond individual projects. In effect, the Mogami program will tie Australian and Japanese naval capabilities together for decades.

The geographic logic underpinning this is clear. Both Australia and Japan are maritime trading nations whose economic interests run through the Indo-Pacific’s sea lanes. Both are increasingly concerned about the implications of China’s growing naval power and its willingness to assert control over these critical waterways. 

Given its isolation, the Australia’s navy requires ships that can operate across enormous distances. The Mogami class, with its extended range and multi-mission flexibility, is designed precisely for this environment – capable of operating across vast distances while being able to be deployed of a range of different missions.

By linking design, production, and maintenance across borders, agreements like this creates a form of interdependence that is hard to reverse. Over time, this draws Australia and Japan closer together not only in terms of aligned worldviews and strategies, but in the practical choices they make – binding the two countries into a far closer, more trusting, relationship, within an era when such relationships between other previously well-aligned countries are starting to fray. 

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Last week Australia and Japan signed a new agreement for the Australian Navy to acquire Japanese-designed Mogami-class frigates. The agreement follows up on the Albanese government’s decision last August to award the project to Japan’s Mitsubishi Heavy Industries (MHI). Countries like Australia are seeking to diversify their military hardware away from the United States, as the deal demonstrates. Canberra and Tokyo continue to build closer links with each other, with a shared understanding of the strategic environment, and a high degree of trust. 

The deal addresses a significant Australian capability gap. Australia’s ageing Anzac-class frigates are increasingly vulnerable in an era defined by long-range precision strike, drones, and undersea competition. The Mogami-class vessels are designed with stealth characteristics, advanced sensors, and the capability to serve a range of different missions. This is a significant upgrade, enhancing anti-submarine warfare, air defense, and greater long-range strike capabilities. 

The planned fleet will consist of 11 vessels, with the first three constructed in Japan and the remainder in Western Australia. This is consistent with Australia’s new approach to defense hardware, which seeks to build local construction capabilities and seek significant technological transfer. For Tokyo, this is a big step, as it usually is incredibly cautious about sharing technology. 

Alongside the practical implications, there is a symbolic element. This is the largest defense hardware agreement since Japan lifted its arms export ban in 2014, signaling a high degree of trust between Tokyo and Canberra. This marks a further step for Japan in normalizing its role as a military power. 

The Australia-Japan relationship has undergone a significant transformation over the past two decades. Once defined primarily by trade – particularly energy exports from Australia to Japan – it has evolved into an increasingly intimate defense relationship. 

This trajectory accelerated after Japan’s 2014 relaxation of its arms export restrictions, which allowed Tokyo to begin participating in international defense markets. The Mogami deal is, in this sense, a culmination of that shift: Japan is no longer just a security consumer under the U.S. alliance system, but an increasingly active provider of security capabilities.

Although Australia continues to bet on an unreliable United States as the central pillar of its defense posture, the new National Defense Strategy does recognize the need to deepen partnerships with other powers in the Indo-Pacific, with Japan being the prime “key partner.” There is an understanding that middle powers must demonstrate the capability to contribute meaningfully to regional security. It is likely that Australia’s Defense Department realizes that Washington is now unreliable; it’s just unwilling to say so openly.

The frigate deal embeds middle power cooperation into industrial practice. The decision to build eight of the vessels in Western Australia is not merely about domestic jobs and enhancing Australia’s defense industry; it represents a deeper integration of defense industrial bases. It is about building the habits of cooperation within the full spectrum defense activity from the shop floor up to coordinated strategy and exercises.  

This has long-term implications. Defense industrial cooperation tends to create path dependencies: shared supply chains, common maintenance requirements, and aligned upgrade cycles. Over time, these generate an integration that extends beyond individual projects. In effect, the Mogami program will tie Australian and Japanese naval capabilities together for decades.

The geographic logic underpinning this is clear. Both Australia and Japan are maritime trading nations whose economic interests run through the Indo-Pacific’s sea lanes. Both are increasingly concerned about the implications of China’s growing naval power and its willingness to assert control over these critical waterways. 

Given its isolation, the Australia’s navy requires ships that can operate across enormous distances. The Mogami class, with its extended range and multi-mission flexibility, is designed precisely for this environment – capable of operating across vast distances while being able to be deployed of a range of different missions.

By linking design, production, and maintenance across borders, agreements like this creates a form of interdependence that is hard to reverse. Over time, this draws Australia and Japan closer together not only in terms of aligned worldviews and strategies, but in the practical choices they make – binding the two countries into a far closer, more trusting, relationship, within an era when such relationships between other previously well-aligned countries are starting to fray. 

Grant Wyeth is a Melbourne-based political analyst specializing in Australia and the Pacific, India and Canada.

Australia-Japan defense deal

Australia-Japan defense relations

Australia-Japan relations

Mogami-class frigates

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